1 // Allocator that wraps "C" malloc -*- C++ -*- 2 3 // Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009 4 // Free Software Foundation, Inc. 5 // 6 // This file is part of the GNU ISO C++ Library. This library is free 7 // software; you can redistribute it and/or modify it under the 8 // terms of the GNU General Public License as published by the 9 // Free Software Foundation; either version 3, or (at your option) 10 // any later version. 11 12 // This library is distributed in the hope that it will be useful, 13 // but WITHOUT ANY WARRANTY; without even the implied warranty of 14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 // GNU General Public License for more details. 16 17 // Under Section 7 of GPL version 3, you are granted additional 18 // permissions described in the GCC Runtime Library Exception, version 19 // 3.1, as published by the Free Software Foundation. 20 21 // You should have received a copy of the GNU General Public License and 22 // a copy of the GCC Runtime Library Exception along with this program; 23 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see 24 // <http://www.gnu.org/licenses/>. 25 26 /** @file ext/malloc_allocator.h 27 * This file is a GNU extension to the Standard C++ Library. 28 */ 29 30 #ifndef _MALLOC_ALLOCATOR_H 31 #define _MALLOC_ALLOCATOR_H 1 32 33 #include <cstdlib> 34 #include <new> 35 #include <bits/functexcept.h> 36 #include <bits/move.h> 37 38 _GLIBCXX_BEGIN_NAMESPACE(__gnu_cxx) 39 40 using std::size_t; 41 using std::ptrdiff_t; 42 43 /** 44 * @brief An allocator that uses malloc. 45 * @ingroup allocators 46 * 47 * This is precisely the allocator defined in the C++ Standard. 48 * - all allocation calls malloc 49 * - all deallocation calls free 50 */ 51 template<typename _Tp> 52 class malloc_allocator 53 { 54 public: 55 typedef size_t size_type; 56 typedef ptrdiff_t difference_type; 57 typedef _Tp* pointer; 58 typedef const _Tp* const_pointer; 59 typedef _Tp& reference; 60 typedef const _Tp& const_reference; 61 typedef _Tp value_type; 62 63 template<typename _Tp1> 64 struct rebind 65 { typedef malloc_allocator<_Tp1> other; }; 66 67 malloc_allocator() throw() { } 68 69 malloc_allocator(const malloc_allocator&) throw() { } 70 71 template<typename _Tp1> 72 malloc_allocator(const malloc_allocator<_Tp1>&) throw() { } 73 74 ~malloc_allocator() throw() { } 75 76 pointer 77 address(reference __x) const { return &__x; } 78 79 const_pointer 80 address(const_reference __x) const { return &__x; } 81 82 // NB: __n is permitted to be 0. The C++ standard says nothing 83 // about what the return value is when __n == 0. 84 pointer 85 allocate(size_type __n, const void* = 0) 86 { 87 if (__builtin_expect(__n > this->max_size(), false)) 88 std::__throw_bad_alloc(); 89 90 pointer __ret = static_cast<_Tp*>(std::malloc(__n * sizeof(_Tp))); 91 if (!__ret) 92 std::__throw_bad_alloc(); 93 return __ret; 94 } 95 96 // __p is not permitted to be a null pointer. 97 void 98 deallocate(pointer __p, size_type) 99 { std::free(static_cast<void*>(__p)); } 100 101 size_type 102 max_size() const throw() 103 { return size_t(-1) / sizeof(_Tp); } 104 105 // _GLIBCXX_RESOLVE_LIB_DEFECTS 106 // 402. wrong new expression in [some_] allocator::construct 107 void 108 construct(pointer __p, const _Tp& __val) 109 { ::new((void *)__p) value_type(__val); } 110 111 #ifdef __GXX_EXPERIMENTAL_CXX0X__ 112 template<typename... _Args> 113 void 114 construct(pointer __p, _Args&&... __args) 115 { ::new((void *)__p) _Tp(std::forward<_Args>(__args)...); } 116 #endif 117 118 void 119 destroy(pointer __p) { __p->~_Tp(); } 120 }; 121 122 template<typename _Tp> 123 inline bool 124 operator==(const malloc_allocator<_Tp>&, const malloc_allocator<_Tp>&) 125 { return true; } 126 127 template<typename _Tp> 128 inline bool 129 operator!=(const malloc_allocator<_Tp>&, const malloc_allocator<_Tp>&) 130 { return false; } 131 132 _GLIBCXX_END_NAMESPACE 133 134 #endif 135
